Human reliability analysis: exploring the intellectual structure of a research field

Humans play a crucial role in modern socio-technical systems. Rooted in reliability engineering, the discipline of Human Reliability Analysis (HRA) has been broadly applied in a variety of domains in order to understand, manage and prevent the potential for human errors. This paper investigates the existing literature pertaining to HRA and aims to provide clarity in the research field by synthesizing the literature in a systematic way through systematic bibliometric analyses. The multi-method approach followed in this research combines factor analysis, multi-dimensional scaling, and bibliometric mapping to identify main HRA research areas. This document reviews over 1200 contributions, with the ultimate goal of identifying current research streams and outlining the potential for future research via a large-scale analysis of contributions indexed in Scopus database

Emerging I&C Technologies Under the Shifting Regulatory Environment in South Korea

The role of Probabilistic Safety Assessment (PSA) has been supplementary and Risk-Informed Applications (RIAs) based on the insight from PSA has also been utilized limitedly in the licensing process for Nuclear Power Plants (NPPs) in South Korea. However, as the technical significance of PSA is getting increased, PSA has become a mandatory part of Safety Analysis Reports and Periodic Safety Review. It is worthwhile to highlight the role of emerging Instrumentation and Control (I&C) technologies including human-machine interface (HMI) in developing more credible and realistic PSA models. Particularly, it is expected that the information technology (i.e. software) embedded in digital I&C can adjust over- and under conservatism in analyzing risk. In this study, authors proposed the cases which would be able to significantly reduce risk if advanced I&C supported by information technologies is applied. In regard, the several enabling techniques and their effects are proposed. In order to improve the commercial competitiveness of NPPs, the need of collaboration and synergetic outcome of I&C, HMI and PSA should be emphasized

INTEGRATED DETERMINISTIC AND PROBABILISTIC SAFETY ANALYSIS: CONCEPTS, CHALLENGES, RESEARCH DIRECTIONS

International audienceIntegrated deterministic and probabilistic safety analysis (IDPSA) is conceived as a way to analyze the evolution of accident scenarios in complex dynamic systems, like nuclear, aerospace and process ones, accounting for the mutual interactions between the failure and recovery of system components, the evolving physical processes, the control and operator actions, the software and firmware. In spite of the potential offered by IDPSA, several challenges need to be effectively addressed for its development and practical deployment. In this paper, we give an overview of these and discuss the related implications in terms of research perspectives

ZINTEGROWANY PROCES DECYZYJNY UWZGLĘDNIAJĄCY RYZYKO W PRZEMYŚLE JĄDROWYM

The regulatory body, established to ensure safety of nuclear facilities, is expected to make right decisions and provide appropriate regulations for the nuclear industry. The traditional manner of its activity has been based on a deterministic approach to safety analyses. However, increased maturity of Probabilistic Safety Assessment (PSA) makes it complementary to deterministic studies. The new IAEA concept, described in this article, is to apply an integrated approach by combining both deterministic and probabilistic insights with other requirements affecting the decision making process.Organ regulacyjny, powołany w celu zapewnienia bezpieczeństwa jądrowego, jest odpowiedzialny za podejmowanie decyzji i wprowadzanie rozporządzeń dla przemysłu jądrowego. Tradycyjny sposób jego funkcjonowania opiera się na deterministycznym podejściu do analiz bezpieczeństwa. Rozwój analiz probabilistycznych (PSA) sprawia jednak, iż są one traktowane jako podejście komplementarne. Nowa koncepcja IAEA, opisana w tym artykule, polega na zintegrowanym podejściu, uwzględniającym analizy deterministyczne, probabilistyczne i inne aspekty procesu decyzyjnego

Dynamic HRA in outage from literature and outage personnel interview perspectives

In 2021, the goal of the SAFIR2022 project NAPRA task T3.2 was to provide an overview of an outage of a nuclear power plant from the perspective of human reliability analysis (HRA). The general features of the outage as well as the specific matters related to human reliability and dynamism in the outage context were studied from literature and outage personnel interview perspectives.The safety-critical nature of an outage is well recognized, and there is a wealth of literature on the specifics of outage and the challenges associated with the successful completion of work. HRA methods have mostly been developed for full power conditions where the operator’s actions are well trained and laid down in procedures, in time frames typically less than 60 minutes. In the planned shutdown the work concentrates outside the control room, is less in procedures and less trained and the time frames may be much longer. The environment is continuously changing, there are huge number of workers, large variety of work activities, tight schedule and the requirements are high concerning both safety and productivity. The key issues that should be considered in the HRA are errors of commission (EOCs), dependencies between human actions and the dynamism of the operating environment.One practical objective of this report was to identify a scenario to focus on in further work related to dynamic modelling. Based on interviews, heavy loads were identified as critical but also mentally and physically loaded. They also include features identified safety critical in scientific literature. This scenario will be studied in more detail in 2022. Work analysis will be performed with special emphasis on applying a combination of methods to elicit the key dynamic features from the HRA perspective

Conjugating ALARA, BEPU, Safety Margins and Independent Assessment in Nuclear Reactor Safety

ALARA (As-Low-As-Reasonably-Achievable) is an early principle in Nuclear Reactor Safety, NRS (Nuclear Reactor Safety): Designers and Operators must do their best to minimize doses to the humans. BEPU (Best Estimate Plus Uncertainty) is an approach in Accident Analysis, part of NRS: one may state that BEPU implies the best use of computational tools to determine the safety of nuclear installations. Then, ALARA may be seen at the origin of BEPU, or ALARA is at the origin of BEPU. Furthermore, BEPU (and BEPU elements like V & V, Scaling, procedures of code application and code coupling, etc.) can be extended to all analytical parts of the Final Safety Analysis Report (FSAR). This brings to BEPU-FSAR. Safety Margin (SM) is an established concept in NRS: a few dozen SM values must be calculated in current safety analyses and demonstrated to be acceptable. The SM concept can be extended to everything part of the design, the operation and the environment for a Nuclear Power Plant (NPP) Unit. Here the environment includes the personnel in charge of activities connected with the NPP. The Extended SM concept, E-SM, implies the formulation of some ten-thousands SM values, which shall correspond to a similar number of monitored variables. Reasons for E-SM are the examples in section 4.1. Independent Assessment (IA) is an early requirement in NRS: data ownership and system complexity prevented so far a comprehensive application of the requirement. IA analyses conflict with industry policies to keep proprietary data. IA based BEPU-FSAR analyses are essential to finalize the E-SM design. In the paper we discuss that: a) ALARA is at the origin of BEPU; b) BEPU-FSAR analyses are the natural origin of E-SM values; c) The implementation of E-SM equals to introducing an additional physical barrier against the release of fission products

Methodological developments for probabilistic risk analyses of socio-technical systems

International audienceNowadays, the risk analysis of critical systems cannot be focused only on a technical point of view. Indeed, several major accidents have changed this initial way of thinking. As a result, there exist numerous methods that allow to study risks by considering on the main system resources: the technical process, the operator constraining this process, and the organisation conditioning human actions. However, few works propose to jointly use these different methods to study risks in a global approach. In that way, this paper presents a methodology, which is under development between CRAN, EDF and INERIS, allowing an integration of these different methods to probabilistically estimate risks. This integration is based on unification and structuring knowledge concepts; and the quantitative aspect is achieved through the use of Bayesian Networks. An application of this methodology, on an industrial case, demonstrates its feasibility and concludes on model capacities, which are about the necessary consideration of the whole causes for a system weakness treatment, and the classification of these contributors considering their criticality for this system. This tool can thus be used to help decision makers to prioritise their actions